Police are appealing for help after a man threatened staff at two service stations in Berkshire Park and Marsden Park overnight.
Detectives have been told the man entered a service station on Richmond Road, Berkshire Park at about 8.30pm on Tuesday (December 5).
It was believed he was armed with a weapon under his shirt.
He allegedly threatened a male employee but fled the scene empty-handed in a dark red Toyota Corolla with obscured number plates.
A short time later, a man entered a Marsden Park service station on Garfield Road West with a suspected weapon under his shirt and stole cash.
No one was injured in either incident.
Penrith police are investigating and believe the two incidents are linked.
Officers wish to speak with a man who may able to assist with their inquiries.
He has been described as being of Caucasian appearance, aged in his 40s, of a large build and wearing a blue shirt and shorts.
Anyone with information is urged to come forward via Crime Stoppers on 1800 333 000.